"Your Browser sent a request that this server could not understand" what does it mean

Wrong request, your browser sends a request that the server cannot understand.

The size of a request header field exceeds the server limit.

In short, this is a server internal error, you can change a website to visit

Your browser sent a request to an unknown server.

This should not be a virus, feel more like a browser Control!

The wrong request

Your browser sends a request that the server cannot understand.

The size of a request header field exceeds the server limit.

Another friend's tip

This is the time to deploy the program to the APACHE2 server, which often occurs when debugging a program

Your Browser sent a request that this server could not understand.

The Size of a request header field exceeds server limit.

The beginning was to set cookies for the P3P protocol, look up the documentation for the P3P, and there are no related entries. After unremitting search, finally found that the original is the use of Apache resource restrictions on the setup issue.

Technical background:

"Resource usage restriction" in Apache is to restrict user access to site-specific resources, such as directories, server hardware, and so on. Relevant directives include: Limitrequestbody, Limitrequestfields, Limitrequestfieldsize, Limitrequestline, Rlimitcpu, RLimitMEM, Rlimitnproc and Threadstacksize. The limitrequest* series directive is used to limit the amount of resources that Apache uses in the process of reading client requests. By limiting these values, some denial of service (DOS) attacks can be mitigated; The rlimit* series instruction restricts the number of resources used by processes that are derived from the Apache subprocess, which are typically used to control the resources used by CGI scripts and SSI EXEC commands; The threadstacksize directive is used on some platforms to control the stack size.

Limitrequestline

The limitrequestline directive is used to limit the number of bytes of HTTP request rows sent by the receiving client, allowing the server administrator to increase or decrease the allowable size limit of the client HTTP request line. Because the request line includes the HTTP method, URI, protocol version, the Limitrequestline directive restricts the length of the request URI. The server would need this value to be large enough to load all of its resource names, including all the information that might be passed in a GET request.

Limitrequestfieldsize

The limitrequestfieldsize directive is used to limit the number of bytes sent by the client to the request header, allowing the server administrator to increase or reduce the size of the HTTP request header domain. In general, the server needs this value to be large enough to accommodate the size of the header domain of any request from a normal client. The size of a common header field is very different for various clients, and is generally associated with users configuring their browsers to support more content protocols.

The Limitrequestline and limitrequestfieldsize directives give the server administrator greater controllability to control the client's abnormal request behavior. This helps to avoid certain forms of denial of service attacks. The default value is "8190".

Solve

Add the following 2 lines of code to the Apache httpd.conf configuration file

Limitrequestline 40940

Limitrequestfieldsize 40940